Lattice parameters and melting behavior of the B2-phase in the ternary gold-cadmium-zinc system

Lattice parameter and DTA-measurements were performed in the range of the ternary B 2-phase in the gold-cadmium-zinc system. It could be shown that a continuous range of homogeneity exists between β′-AuCd and β′-AuZn. Lattice parameter values are reported for a number of compositions. The ternary liquidus projection is given between about 40 and 60 at % Au. The congruent melting point of the binary β′-AuZn phase was found to be at 51.5±0.5 at % Au and 758±3°C.     

The Effect of Ge, Ni, and Fe Doping on the Ga Activity in the CoGa B2 Phase

Gallium activity in the B2 (CsCl-type) phase of ternary Co–Ga–X (X = Ge, Ni, and Fe) alloys was measured by the EMF method with a stabilized zirconia solid electrolyte. The temperature range was 1050–1250 K and the concentrations of the added elements were 2–6 at-% Ge and Ni, and 1–3 at-% Fe. The reference electrodes were Fe,Fe_xO or Ga,Ga₂O₃. The effect on the activity of gallium in the B2 phase with the addition of other elements was found to be the largest with Ge and the smallest in the case of Ni.     

Effect of Ti pretreatment on photoelectric properties of TiO2 layers prepared by plasma-anodic oxidation

Photoactive TiO₂ layers were formed by anodic oxidation of Ti in O₂ RF plasma under various conditions and Ti surface pretreatment. The photocurrent spectrum in 1M NaOH was used to calculate the quantum efficiency of the photocurrent production and the band-gap energy for indirect transitions. Photoelectrochemical properties of TiO₂ layers were studied on the decomposition of p-cresol water solution. The method of Ti surface pretreatment (mechanical polishing or chemical etching) has a decisive influence on the photoelectrochemical properties and the structure of the polycrystalline oxide, rutile, anatase or amorphous phase content.This study was supported by the Grant Agency for Sciences of Slovakia.     

The density and surface tension of In–Sn and Cu–In–Sn alloys

Abstract  

The density and surface tension of binary In–Sn and ternary Cu–In–Sn alloys have been measured by a sessile-drop method. Decrease of the density and of the surface tension was observed with rising temperature. With increased Sn content in the alloys, the density increased while the surface tension reduced slightly. Addition of Cu could significantly increase the density and surface tension in the Cu–In–Sn system. The surface tension of the Cu–In–Sn alloys was also calculated by means of Butler’s equation, and compared with experimental values, showing good agreement.     

Strong biaxial texture and polymorph nature in TiO2 thin film formed by ex-situ annealing on c-plane Al2O3 surface

Many applications based on TiO₂ thin films are strongly influenced by the film crystalline quality, microstructure and surface morphology. We have utilized x-ray scattering methods for crystal structure study of TiO₂ films, grown by DC reactive magnetron sputtering without heating. We have observed the formation of ordered phases after post-deposition ex-situ annealing in air at 600 °C. The distinct biaxial texture with respect to the c-plane (0001) Al₂O₃ substrate surface, which developed during heating, shows remarkable patterns in pole figures. We have identified epitaxial relationships of anatase A(001)[110]6sub(001)[11?00] and rutile R(100)[001]6sub(0001)[100] within single TiO₂ layer. In addition, within the same sample, we have observed the anatase in (112) orientation with two in-plane relationship options A(112)[11?0]6sub(0001)[21?1?0] and A(112)[11?0]6sub(0001)[11?00].     

Preconcentration of Cd(II), Pb(II), Co(II), Ni(II), and Cu(II) by solid-phase extraction method using 1,10-phenanthroline

Solid-phase extraction (SPE) method for preconcentration and determination of Cd(II), Pb(II), Co(II), Ni(II), and Cu(II) aqueous samples by inductively coupled plasma optical emission spectrometry is described. The preconcentration of analytes is accomplished by retention of their chelates with 1.10-phenanthroline in aqueous solution on a solid phase containing carboxylic acid (COOH) bonded to silica gel in a column. The limits of detection values (defined as “3s” where “s” is standard deviation of the blank determination) are 3.6 μg/L for Cd(II), 17.5 μg/L for Pb(II), 3.1 μg/L for Co(II), 2.1 μg/L for Ni(II), and 4.4 μg/L for Cu(II) and corresponding limit of quantification (6s) values are 7.2, 35, 6.2, 4.2 and 8.8 μg/L, respectively. As a result, a simple method was elaborated for the group concentration and determination of the above mentioned metals in reference material and in samples of plant material. The article is published in the original.